.TH "QwtLogScaleEngine" 3 "Wed Jan 2 2019" "Version 6.1.4" "Qwt User's Guide" \" -*- nroff -*-
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.SH NAME
QwtLogScaleEngine \- A scale engine for logarithmic scales\&.  

.SH SYNOPSIS
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.PP
.PP
\fC#include <qwt_scale_engine\&.h>\fP
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Inherits \fBQwtScaleEngine\fP\&.
.SS "Public Member Functions"

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.ti -1c
.RI "\fBQwtLogScaleEngine\fP (uint \fBbase\fP=10)"
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.RI "virtual \fB~QwtLogScaleEngine\fP ()"
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.RI "Destructor\&. "
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.RI "virtual void \fBautoScale\fP (int maxNumSteps, double &x1, double &x2, double &stepSize) const"
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.RI "virtual \fBQwtScaleDiv\fP \fBdivideScale\fP (double x1, double x2, int maxMajorSteps, int maxMinorSteps, double stepSize=0\&.0) const"
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.RI "Calculate a scale division for an interval\&. "
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.SS "Protected Member Functions"

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.RI "\fBQwtInterval\fP \fBalign\fP (const \fBQwtInterval\fP &, double stepSize) const"
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.RI "Align an interval to a step size\&. "
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.RI "void \fBbuildTicks\fP (const \fBQwtInterval\fP &, double stepSize, int maxMinorSteps, QList< double > ticks[\fBQwtScaleDiv::NTickTypes\fP]) const"
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.RI "Calculate ticks for an interval\&. "
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.RI "QList< double > \fBbuildMajorTicks\fP (const \fBQwtInterval\fP &interval, double stepSize) const"
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.RI "Calculate major ticks for an interval\&. "
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.RI "void \fBbuildMinorTicks\fP (const QList< double > &majorTicks, int maxMinorSteps, double stepSize, QList< double > &minorTicks, QList< double > &mediumTicks) const"
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.RI "Calculate minor/medium ticks for major ticks\&. "
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.SS "Additional Inherited Members"
.SH "Detailed Description"
.PP 
A scale engine for logarithmic scales\&. 

The step size is measured in \fIdecades\fP and the major step size will be adjusted to fit the pattern $\left\{ 1,2,3,5\right\} \cdot 10^{n}$, where n is a natural number including zero\&.
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\fBWarning:\fP
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the step size as well as the margins are measured in \fIdecades\fP\&. 
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.SH "Constructor & Destructor Documentation"
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.SS "QwtLogScaleEngine::QwtLogScaleEngine (uint base = \fC10\fP)"
Constructor
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\fBParameters:\fP
.RS 4
\fIbase\fP Base of the scale engine 
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\fBSee also:\fP
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\fBsetBase()\fP 
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.SH "Member Function Documentation"
.PP 
.SS "\fBQwtInterval\fP QwtLogScaleEngine::align (const \fBQwtInterval\fP & interval, double stepSize) const\fC [protected]\fP"

.PP
Align an interval to a step size\&. The limits of an interval are aligned that both are integer multiples of the step size\&.
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\fBParameters:\fP
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\fIinterval\fP Interval 
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\fIstepSize\fP Step size
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\fBReturns:\fP
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Aligned interval 
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.SS "void QwtLogScaleEngine::autoScale (int maxNumSteps, double & x1, double & x2, double & stepSize) const\fC [virtual]\fP"
Align and divide an interval
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\fBParameters:\fP
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\fImaxNumSteps\fP Max\&. number of steps 
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\fIx1\fP First limit of the interval (In/Out) 
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\fIx2\fP Second limit of the interval (In/Out) 
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\fIstepSize\fP Step size (Out)
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\fBSee also:\fP
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\fBQwtScaleEngine::setAttribute()\fP 
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.PP

.PP
Implements \fBQwtScaleEngine\fP\&.
.SS "QList< double > QwtLogScaleEngine::buildMajorTicks (const \fBQwtInterval\fP & interval, double stepSize) const\fC [protected]\fP"

.PP
Calculate major ticks for an interval\&. 
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\fBParameters:\fP
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\fIinterval\fP Interval 
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\fIstepSize\fP Step size
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\fBReturns:\fP
.RS 4
Calculated ticks 
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.SS "void QwtLogScaleEngine::buildMinorTicks (const QList< double > & majorTicks, int maxMinorSteps, double stepSize, QList< double > & minorTicks, QList< double > & mediumTicks) const\fC [protected]\fP"

.PP
Calculate minor/medium ticks for major ticks\&. 
.PP
\fBParameters:\fP
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\fImajorTicks\fP Major ticks 
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\fImaxMinorSteps\fP Maximum number of minor steps 
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\fIstepSize\fP Step size 
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\fIminorTicks\fP Array to be filled with the calculated minor ticks 
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\fImediumTicks\fP Array to be filled with the calculated medium ticks 
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.SS "void QwtLogScaleEngine::buildTicks (const \fBQwtInterval\fP & interval, double stepSize, int maxMinorSteps, QList< double > ticks[QwtScaleDiv::NTickTypes]) const\fC [protected]\fP"

.PP
Calculate ticks for an interval\&. 
.PP
\fBParameters:\fP
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\fIinterval\fP Interval 
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\fImaxMinorSteps\fP Maximum number of minor steps 
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\fIstepSize\fP Step size 
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\fIticks\fP Arrays to be filled with the calculated ticks
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\fBSee also:\fP
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\fBbuildMajorTicks()\fP, \fBbuildMinorTicks\fP 
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.SS "\fBQwtScaleDiv\fP QwtLogScaleEngine::divideScale (double x1, double x2, int maxMajorSteps, int maxMinorSteps, double stepSize = \fC0\&.0\fP) const\fC [virtual]\fP"

.PP
Calculate a scale division for an interval\&. 
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\fBParameters:\fP
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\fIx1\fP First interval limit 
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\fIx2\fP Second interval limit 
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\fImaxMajorSteps\fP Maximum for the number of major steps 
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\fImaxMinorSteps\fP Maximum number of minor steps 
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\fIstepSize\fP Step size\&. If stepSize == 0, the engine calculates one\&.
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\fBReturns:\fP
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Calculated scale division 
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.PP

.PP
Implements \fBQwtScaleEngine\fP\&.

.SH "Author"
.PP 
Generated automatically by Doxygen for Qwt User's Guide from the source code\&.
